Foma still make a "contact-speed" paper, called Fomalux. That might be worth a look. It is a fibre paper with a slow chloride emulsion. I have two packets for a few months and am ashamed that I haven't tried it yet! The idea was to use 8x10" film pinhole negs (Foma 100) on it, but I still haven't figured out how I'm going to hold the DDS on the back of the home-made camera . . .